body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: url(../images/background.jpg) no-repeat;        /* 背景图片不重复 */
    background-size: cover;         /* 平铺内容 */
    background-position: center;    /* 内容居中 */
}
header {
    position: fixed;
    top: 0;
    left: 0;
    width: 87%;
    padding: 20px 100px;
    /* background: #c19898; */
    display: flex;
    justify-content: space-between;     /* 子元素两边放置 */
    align-items: center;        /* 上下居中 */
    z-index: 99;
}
.logo {
    font-size: 2em;
    color: #fff;
    user-select: none;      /* 字体不能被选中 */
}
.navigation a {
    position: relative;
    font-size: 1.1em;
    color: #fff;
    font-weight: 500;
    margin-left: 40px;
}
.navigation a::after {
    content: '';        /* 插入生成的内容 */
    position: absolute;
    width: 100%;
    height: 3px;
    left: 0;
    bottom: -6px;
    background: #fff;
    border-radius: 5px;
    transform: scaleX(0);       /* 沿x轴方向缩小 */
    transform-origin: right;     /* 设置动画的基点(中心点) */
    transition: 0.5s;
}
.navigation a:hover::after {
    transform: scaleX(1);       /* 沿x轴方向放大 */
    transform-origin: left;     /* 设置动画的基点(中心点) */
}
.navigation .btnLogin-popup {
    width: 130px;
    height: 50px;
    background: transparent;        /* transparent 背景透明 */
    border: 2px solid #fff;
    border-radius: 6px;
    cursor: pointer;                /* 鼠标变成手指 */
    font-size: 1.1em;
    color: #fff;
    font-weight: 500;
    margin-left: 40px;
    transition: 0.5s;
}
.navigation .btnLogin-popup:hover {
    background: #fff;
    color: #162938;
}

/*  */
.wrapper {
    position: relative;
    width: 400px;
    height: 400px;
    background: transparent;
    border: 2px solid rgba(255, 255, 255, 0.5);
    border-radius: 20px;
    backdrop-filter: blur(20px);        /* 滤镜-blur模糊 */
    box-shadow: 0 0 30px rgba(0, 0, 0, 0.5);        /* 边框阴影 */
    display: flex;
    justify-content: center;    /* 控制子元素在主轴居中 */
    align-items: center;    /* 容器垂直居中 */
    text-align: left;       /* 文本居左对齐 */
    overflow: hidden;
    transition: transform 0.6s ease, height 0.2s ease;
    transform: scale(0);        /* 中心缩放 */
}
.wrapper.active-popup {
    transform: scale(1);
}
.wrapper.active {
    height: 520px;
}

.wrapper .form-box {
    width: 100%;
    padding: 40px;
}
.wrapper .form-box.login {
    transition: transform 0.6s ease;
    transform: translateX(0);
}
.wrapper.active .form-box.login {
    transition: 0.6s ease;
    transform: translateX(-400px);
}
.wrapper .form-box.register {
    position: absolute;
    transition: 0.6s ease;
    transform: translateX(400px);
}
.wrapper.active .form-box.register {
    transition: transform 0.6s ease;
    transform: translateX(0);
}
.wrapper .iconClose {
    position: absolute;
    top: 0;
    right: 0;
    width: 45px;
    height: 45px;
    background: #162938;
    display: flex;
    justify-content: center;    /* 控制子元素在左右居中 */
    align-items: center;        /* 垂直方向对齐方式 */
    border-bottom-left-radius: 20px;
    border-top-right-radius: 20px;
    cursor: pointer;
    z-index: 1;
}
.wrapper .iconClose .iconfont {
    font-size: 2em;
    color: #fff;
}
.form-box h2 {
    font-size: 2em;
    color: #162938;
    text-align: center;
}
.input-box {
    position: relative;
    width: 100%;
    height: 50px;
    border-bottom: 2px solid #162938;
    margin: 30px 0;
}
.input-box label {
    position: absolute;
    top: 50%;
    left: 5px;
    transform: translateY(-50%);
    font-size: 1em;
    color: #162938;
    font-weight: 500;
    pointer-events: none;       /* 无法摸的着，点击会穿透触发到下层的元素 */
    transition: 0.7s;
    font-weight: 600;
}
.input-box input:focus~label,       /*产生对应操作时，label发生的样式变化*/
.input-box input:valid~label {
    top: -5px;
    font-weight: 500;
}

.input-box input {
    width: 100%;
    height: 100%;
    background: transparent;
    border: none;
    font-size: 1em;
    color: #162938;
    font-weight: 600;
    padding: 0 35px 0 5px;
}
.input-box .iconfont {
    position: absolute;
    right: 8px;
    font-size: 1.5em;
    color: #162938;
    line-height: 57px;
}
.remember-forgot {
    font-size: 0.9em;
    color: #162938;
    font-weight: 500;
    margin: -15px 0 15px;
    display: flex;
    justify-content: space-between;
}
.remember-forgot label input {
    accent-color: #162938;      /* input中选择框的颜色 */
    margin-right: 3px;
}
.remember-forgot a {
    color: #162938;
}
.remember-forgot a:hover {
    text-decoration: underline;
}
.btn {
    width: 100%;
    height: 45px;
    background: #162938;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 1em;
    color: #fff;
    font-weight: 500;
}
.login-register {
    font-size: 0.9em;
    color: #162938;
    text-align: center;
    font-weight: 500;
    margin: 25px 0 10px;
}
.login-register p a {
    color: #162938;
    font-weight: 600;
}
.login-register p a:hover {
    text-decoration: underline;
}